William Shatner is hilarious. We’ve known it for years, whether it was his super-serious attitude on the original “Star Trek” or his caricature of himself in those Priceline commercials — but you’ll gain a far greater appreciation for it with “Trek Stars Go West,” a collection of TV shows and films that starred “Star Trek” actors in Westerns before and during their time in fake space. Shatner as a peyote-smoking half-white, half-Comanche sociopath is probably the greatest thing you’ve ever seen the former Capt. Kirk do — you know, in a bad way.